Carbohydrates and Health

Methodology
S.4 Only evidence from prospective cohort studies and randomised controlled trials
was considered for this report. SACN commissioned systematic reviews of the
evidence on cardio-metabolic, colo-rectal and oral health in literature published
from 1990 up to and including December 2009, November 2010 and January 2011
respectively. In order to ensure that the evidence base was as current as possible
while SACN was undertaking this review, the literature searches were subsequently
updated for studies on important health outcomes published up to June 2012. The
evidence was assessed using the SACN Framework for the Evaluation of Evidence
and graded according to a system devised specifically for this review.
S.5 SACN has evaluated evidence assessing whether intakes of specific carbohydrates
are a factor in the risk for cardiovascular disease, obesity, type 2 diabetes mellitus
and colo-rectal cancers. The relationship between dietary carbohydrate intake
and a large number of risk factors and markers related to these diseases has been
considered. Evidence on the relationship of carbohydrates to oral health has also
been discussed. For many of the risk factors and disease markers identified, there
was insufficient evidence of the required quality, therefore SACN has based its
recommendations on those conclusions where the committee considered the
evidence base to be of sufficient standard according to the SACN Framework for
the Evaluation of Evidence and the grading system developed for this review.
S.6 In this report, evidence has been considered under the broad headings of total
carbohydrates; sugars and sugars-sweetened foods and beverages; starch and
starch-rich foods; dietary fibre; non-digestible oligosaccharides, resistant starch,
polyols and polydextrose; and the glycaemic characteristics of carbohydrate-rich
foods and diets (glycaemic index and glycaemic load). The individual chapters
provide extensive detail on the evidence considered for each type of carbohydrate
in relation to health outcomes, SACN’s view of the strength of the evidence and
its conclusions.
Conclusions and recommendations
S.7 The main findings of this review of the evidence on carbohydrates and health,
upon which SACN has based its recommendations, are set out below. The report
provides a detailed consideration of all the evidence considered by SACN.
Total dietary carbohydrate
S.8 Overall, the evidence from both prospective cohort studies and randomised
controlled trials indicates that total carbohydrate intake appears to be neither
detrimental nor beneficial to cardio-metabolic health, colo-rectal health and
oral health. However, this report highlights that there are specific components
or sources of carbohydrates which are associated with other beneficial or
detrimental health effects. The hypothesis that diets higher in total carbohydrate
cause weight gain is not supported by the evidence from randomised controlled
trials considered in this review.
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